Answered: How to retain previous filter on checkbox extjs 4.1

Hey everyone... I am trying to use this checkbox filter... where a user clicks and then shows list of states on a grid that's only cold... when the user unchecks, I want the store to be back on the previous state... I don't want to use the store.clearfilter() because it just clears my previous filter... I want to retain the previous filter (which is triggered from another combox)... Here's my code that i am trying to use.. but it says